Methanol → Drometrizole

HRID 1763175Notes

Reaction equation

HRID 1763175 reaction equation
CO.O=C[C@@H]([C@H]([C@@H]([C@@H](CO)O)O)O)O.[OH:15][C:16]1[CH:21]=[CH:20][C:19]([CH3:22])=[CH:18][C:17]=1[N:23]1[N+:27]([O-])=[C:26]2[CH:29]=[CH:30][CH:31]=[CH:32][C:25]2=[N:24]1.S(=O)(=O)(O)O>O>[OH:15][C:16]1[CH:21]=[CH:20][C:19]([CH3:22])=[CH:18][C:17]=1[N:23]1[N:27]=[C:26]2[CH:29]=[CH:30][CH:31]=[CH:32][C:25]2=[N:24]1

Participants

6

Reactant 4

HCID 887MethanolHCID 1118Sulfuric AcidHCID 107526(2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanalHCID 132146462-(2-hydroxy-5-methylphenyl)benztriazole N-oxide

Product 1

HCID 17113DrometrizoleYield 92.8%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To the wet product 12 g thus obtained, were added methanol 60 ml, water 30 ml, 97% sodium hydroxide 13.0 g and 9-fluorene 0.5 g, and glucose 5.5 g was further added to the mixture over one hour while stirring at 50° to 55° C. The mixture was reacted while stirring at 75° C. (boiling point) for 5 hours. As this result, the N-oxide disappeared, thus Process (c) being completed. The reaction liquor was neutralized with 62% sulfuric acid 19.8 g to pH 8 to precipitate a crystal. The precipitated crystal was separated by filtration, and the separated crystal was fully washed with water and further with methanol. The washed crystal was then dried, thus obtaining 9.4 g of 2-(2'-hydroxy-5'-methylphenyl)benzotriazole having a melting point of 128° to 130° C. at the yield of 92.8%.

Workup

  1. additionwas further added to the mixture over one hour
  2. customThe mixture was reacted
  3. stirringwhile stirring at 75° C. (boiling point) for 5 hours
  4. customto precipitate a crystal
  5. customThe precipitated crystal was separated by filtration
  6. washthe separated crystal was fully washed with water and further with methanol
  7. customThe washed crystal was then dried

Sources & evidence

ORD record
ord-1164d98aaaa8443ebdb709d62bc0d14e
Source dataset
uspto-grants-1989_05
Patent number
US04835284

Reaction notes

Loading…